Generally, a hot water boiler, which heats water by using gas or electricity, has an internal pipe having a cold water introduction portion connected to a water supply source at one side thereof and a hot water discharge portion connected to a building pipe at the other side thereof. The cold water supplied to the hot water boiler through the cold water introduction portion is heated by means a gas burner or electric heater, while being passed through the internal pipe in the hot water boiler.
One conventional device for washing an internal pipe in a hot water boiler has been disclosed in U.S. Pat. No. 7,621,255, but the conventional device is configured to rotate a ball valve body in the interior of a body by means of a lever, so that the ball valve body adheres to the body, thus making it hard to operate the lever normally.
Through many studies, accordingly, this inventor has proposed a new valve device that is simple in configuration so that it can be easily mounted on a restricted installation area and that is provided with an operating part which is not brought into contact with a body so that even though the valve device is not used for a long period of time, the operating part does not adhere to the body.